Labeling, i.e. matching anatomical textbook information to a segmented object, is crucial for a complete medical report but is often performed manually in an ad-hoc manner due to time constraints, or automatically, in which case labeling often fails when presented with non-standard anatomy or bad or uncommon scans.
Current image processing workstations and Picture Archiving and Communication Systems (PACS) offer all kinds of segmentation tools for tree-like structures, such as vessels. These segmentation tools utilize techniques such as region growers, include and exclude seed strategies, thresholds, and statistical or model-based learning. Besides the segmentation tools and methods, there have been some attempts towards automatic labeling based on anatomical reference models, such as atlases.
FIG. 1 illustrates an example of combined tree segmentation and an atlas of the bronchial tree. The left portion of FIG. 1 shows a segmentation of the bronchial tree. The right portion of FIG. 1 shows an atlas with the nomenclature of the bronchial airway tree.
Currently, even when the segmentation tool is working adequately, the labeling task will be difficult because the diversity in “normal anatomical” structures can be very large. In case of missing tree segments, which will be the case in the analysis of trees with obstructions, it is even harder to perform automatic labeling. Automatic labeling also requires that the segmented tree structure is presented in an “anatomical” way. Segmentation tools often provide small branches in a standard graph-like structure. Anatomically there will be a main branch and several sub branches that originate from that main branch. A label or anatomical name belongs to a main branch that may consist of several branching levels in the detected graph.
Current solutions are either ad-hoc or automatic. In ad hoc solutions, not all is labeled but only two or three places are labeled since labeling takes time, and the user often has limited time for these tasks. This means for example that the segmenting is performed only near a stenotic region instead of being applied to a whole vessel, after which manual labeling of the small region is performed.
In some current manual labeling techniques a path found by a segmentation tool may be selected and a name may be assigned from a list. Once selected, the name disappears from the list.
Automatic labeling will often fail in non-standard anatomy and/or bad or uncommon scans, in which case an easy correction is not offered.
Hence, an improved labeling method, apparatus, graphical user interface, computer-readable medium, and use would be advantageous, allowing for increased flexibility, and cost-effectiveness.